A conventional flat bed knitting machine generally has a front needle bed and a rear needle bed. During knitting operation one of the needle beds can be used to do technical face knitting, or the front and rear needle beds also can be used at the same time interchangeably to do technical face knitting or interlocked double faces knitting. The technical face knitting also is called plain stitch. The knitting fabrics it produced have a technical face to be used as the front face of the fabrics. Plating also is called yarn adding or yarn stacking, and is a process by feeding two yarns of different colors at the same time during the knitting operation to produce a fabric with different colors on the technical face and a technical back. In order to increase fabric color changes or pattern variations a technique of feeding two different colors of yarns at the same time and doing plain stitch at the front needle bed and reverse stitch at the rear needle bed to form plating to generate the color changes or pattern variations of the fabric also is available at present. Namely, the present knitting technique can produce fabrics with plating on the technical back interwoven in the plating on the technical face in a predetermined segment, and the plating of the technical back appeared on the technical face can be used as the front face of the fabric. The fabric with the plating formed via reverse stitch has a back side structure and different colors of plating on the technical back to form Jacquard effect on the plating of the technical face like a Jacquard fabric.
It is generally known that the market requires the knitted fabrics to have different color changes and pattern variations. However, the fabric producers, in order to save production time and reduce knitting cost and increase production yield, often adopt the foresaid conventional technique to produce technical face plain stitch fabrics with plating on the technical back to meet market requirements. But the fabrics produced via the present technique cannot fully meet consumers' requirements. The main reason is that the structural appearance of the plating on the technical back of the technical face plain stitch fabric that adopted the present technique is different from that of the plating on the technical face. People with a general aesthetic sense can easily see the unmatched structural appearances of the two and feel it like the technical face of the fabric has been smeared by objects of different colors. Hence the fabric thus made has lost its appeal to the consumers. It urgently needs improvement to resolve this problem in the industry.